Boost C++ Libraries: Ticket #3388: Default to parallel build

component changed; owner set

Steven Watanabe — Wed, 02 Sep 2009 14:59:53 GMT

owner set to René Rivera
component None → bjam

I prefer the default of a non-parallel build. It is more obvious and is consistent with other build tools.

anonymous — Wed, 02 Sep 2009 15:11:16 GMT

Why is it more obvious?

Unfortunately, yes, most other tools default to serial execution as well. :(

status changed; resolution set

Vladimir Prus — Tue, 10 Nov 2009 07:36:15 GMT

status new → closed
resolution → wontfix

Given that it's already possible to set per-user default by putting

option jobs : 4 ;

in any config file, and given that making parallel build the default is controversial, I guess I'll close this issue.

Tino — Mon, 11 Feb 2013 09:07:39 GMT

Additionally, parallel builds can only be hardcoded to a specific number. AFAIK bjam can not use a make jobserver in the case that boost is only one part of the whole build process.

I have a build system that builds several software packages for several architectures in one run. I can specify make -j<number> and the make jobserver will use the specified number of jobs.

Except for Boost. I have to hardcode a fixed job number for the boost build (like bjam -j4), that leads to either unused CPU cores, or a lot of overhead, depending on the number of target architectures that are built and the number of CPU cores usable.

Vladimir Prus — Mon, 11 Feb 2013 09:27:01 GMT

Tino,

it's not clear to me what you propose? Making b2 interact with make processes running at part of your bigger build does not seem easy.